Art of making lead protoxide



(No Model.)

G. D. COLEMAN.

ART OF MAKING LEAD PROTOXIDE. No. 481,005.

Patented Aug. 16, 1892.

A INVENTOR:

TTESTI GeoryeZlC'oZemczn Nirnn STATES FATENT rFicE.

ART OF MAKING LEAD PROTOXIDE.

SPECIFICATION forming part of Letters Patent No.481,005, dated August 16, 1892.

Application filed August 17, 1891- Serial No. 402,923. (No specimens.)

To all whom it may concern.-

Be it known that I, GEORGE D. COLEMAN, a citizen of the United States, residing at Ohicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in the Art of Making Lead Protoxide; and Ido hereby declare the followingto be afull, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to use and carry on the same.

This invention relates to the production of lead protoxide by what is generally known as the attrition process, in which metallic lead in a comminuted state is exposed to agitation in the presence of water and atmospheric air ito 2e gradually oxidized into a protoxide of My present improvement on such wellknown process of making lead protoxide consists, first, in carrying on the process Within a suitable closed vessel and at a regulated temperature of from to 150 Fahrenheit, and, secondly, in the use of a regulated flow of water through the corroding-vessel for the different purposes of holding the temperature at the degree of heat desired; also, to remove the protoxide as fast as formed and leave the particles of metallic lead in 'a bright condition best adapted for oxidation.

In the practical carrying out of my present improvement I make use of any suitable closed vessel, preferably a closed rotating vessel or drum, as illustrated I in the accompanying drawings, the apparatus so illustrated forming the subject-matter of a separate application for Letters Patent filed by me August 17, 1891, Serial No. 402,921.

In the drawings, Figure 1 is a longitudinal sectional elevation of the corroding apparatus; Fig. 2, a transverse sectional elevation at line 00 at, Fig. 1; Fig. 3, a detached sectional elevation of the mechanism for imparting motion to the automatic feeding device for the comminuted lead; Fig. 1-, an enlarged detail section of theautomatic feedingdevice pro per Fig. 5, an enlarged detail transverse section of the gas and Water pipes within the cylinder; Fig. 6, a detail section of a part of the wall of the cylinder, showing the relative arrangement of the longitudinal ribs on the inner periphery of the same.

Similar numerals of reference indicate like parts in the different Views.

Referring to the drawings, 1 represents the horizontally-arranged corroding cylinder or drum, of wood or metal, as desired, and provided with axial trunnions, by which it is journaled to rotate in the end standards 2 of a suitable frame 3, continuous rotary motion being imparted to the cylinder in any suitable and well-known manner, preferably by a counter-shaft 4, supported in bearings in the standards 2, pinions 6, and gears '7 and 8.

9 is a manhole at one or both ends of the cylinder for access to the interior of the same and through which the supply of oomminuted lead can be introduced in the initial starting of the apparatus, the subsequent supply being effected automatically and continuously by automatic feeding mechanism hereinafter more fully described.

The inner periphery of the cylinder or drum 1 will be lined with any suitable incorrodible material, preferably sheet-brass, and provided with a series of longitudinal ribs or bars 10, having an oblong square formation and arranged in close relation to each other,

as illustrated in Fig. 6, so as to leave a space or cavity between adjacent ribs of a width about equal to the Width of the top face of a rib or bar 10. This arrangement provides narrow longitudinal cavities around the inner periphery that fill with a body of the lead particles at their lower positions and hold the same to form a frictional surface even with the tops of the ribs. In this manner wear upon the ribs is restricted to the top surfaces of the ribs alone, and in consequence the lifetime of the ribs is extended to a great length.

The trunnions of the corroding-cylinder are made hollow for the passage of the axial pipes, by which the flow of water and gases takes place through the corroding-chamber, leakage being prevented at each cylinderhead around said pipes by means of the stuffing-boxes or glands 11. Said pipes, as illustrated in the drawings, consist of the induction and eduction non-rotary sections of water-pipe 12 and 13 and the similar induction a nd eduction non-rotary sections of gas or air pipe 1a and 15, that are arranged to surround the water-pipe sections, as shown, the induction-pipe sections 12 and 1e being respect- ICO ively perforated and slotted along their length within the interior of the corroding-cylinder, so as to evenly distribute the water and gas along the whole length of such cylinder, while the eduction sections of pipe 13 and 14 communicate with the interior of the corrodingcylinder in the following manner: the aireduction pipe 13 by means of alateral opening 16 and the water-eduction pipe by means of an open-ended down wardly-extendin g branch 17, that dips into the contained water in the corrodingcylinder, said branch pipe being preferably arranged in an oblique direction, so as to take water at a point removed from the end of the corroding-cylinder.

The different pipe-sections 12, 13, 14, 15, and 17 are connected together so as to brace and support each other by means of a hollow Y- shaped plug 18, which affords a very convenient support for the inner ends of the different pipe sections, as clearly indicated in Fig. 1.

The passage of the water induction and eduction pipes 12 and 13 through the ends of the respective air induction and eduction pipes 14 and is effected in a tight manner by means of glands or stuffing-boxes 19 and 20 in the respective couplings of the pipesections 12 and 13, with their inlet and outlet branch pipes 21 and 22, through which the air or other gas is introduced under pressure from a suitable accumulator or other source and discharged into a succeeding corrodingchamber or other escape, as desired, such escape being controlled and regulated by a valve 23. The water eduction or outlet branch pipe is similarly provided with a valve 24, so as to regulate the flow of water through the corroding-cylinder, and in consequence the degree of temperature therein caused by mechanical as well as chemical action, the Water inlet or induction branch 25 being connected to a pump or other suitable source of water pressure supply.

An automatic feeding mechanism, as follows, is provided for introducing a constant and limited supply of comminuted metallic lead to compensate for the amount abstracted in the form of corroded lead. In this 26 is a rotary cylinder receiving an intermittent rotary motion from the driving counter-shaft 4 of the apparatus or other suitable source of motion through the eccentric 27 on said shaft, eccentric-rod 28, and rock-arm 29, carrying a pawl 30, that engages and actuates a ratchetwheel 31, fixed on the hub of the cylinder 25 to efiect the desired intermittent rotation to the same. The rock-arm 29 has pivotal movement on the hub of the cylinder 26, and the connection of the eccentric-rod 28 thereto is adjustable in a radial direction to or from the axis of the cylinder 26, so as to regulate the speed with which the same is rotated. The periphery of the cylinder 26 is formed with a number of pockets or recesses 32, that take a supply of comminuted lead from the upper chamber of the casing 33 of such cylinder to carry it to the lower chamber thereof. In the construction shown the upper chamber is in connection with the supply funnel or hopper 34, while the lower chamber is in communication with the air inlet or induction pipe section 14,int0 which the lead drops to be conveyed by the spiral conveyer 35 forward into the corroding-cylinder.

The spiral conveyor 35 is on a sleeve surrounding the water-induction pipe 12 and passes out through the gland or stuffing-box 19 and is provided with a belt-pulley 36, by which motion is imparted to the spiral conveyer from any suitable source.

37 is a gland or stuffing-box formation for preventing a leakage at the joint between the conveyor-sleeve and the water-induction ipe.

p 38 is a straight-way valve immediately beneath the feeding-cylinder 26 for the purpose of closing the communication between the same and the interior of the corroding-cylinder when it is desired to repair such mechanism or for any other required uses. In such closed vessel I place the required amount of metallic lead in a comminuted or shotted condition and expose the same to an attrition or rolling action in the presence of a sulficient quantity of water and atmospheric air, which is preferably made to flow in an energetic manner through the apparatus, at the same time regulating the flow of water through the apparatus to a faster or slower degree, in accordance with the rapid or slow generation of local heat within the apparatus due to mechanical as well as chemical action, and in such manner preserve in a uniform manner the temperature within the corroding-vessel at the desired point.

I am aware that prior to myinvention lead protoxide has been made by the agitation, in a perforated vessel, of metallic lead in a comminuted state in the presence of water and atmospheric air, the water passing through the perforated walls of the vessel to carry off the oxide as formed. I therefore make no claim to any such process, broadly; but,

Having thus fully described my said invention, what I claim as new, and desire to secure by Letters Patent, is

1. The herein-described improvement in the art of making lead protoxide, which consists, first, in subjecting a body of comminuted lead in a state of agitation within a suitable vessel to the action of atmospheric air and water; secondly, removing the oxide as fast as formed and controlling the temperature during the process by a regulated in flow and outflow of water through the corroding-vessel and its contents,and, thirdly, replacingthelead removed during the process in the form of oxide by a regulated supply of comminuted lead, the supplies of air, water, and comminuted lead being regulated with regard to each other.

2. The herein-described improvement in the art of making lead protoxide, which consists,

form of oxide by a regulated supply of com Ininuted lead, the silpplies of air, water, and comrninuted lead being regulated with regard to each other.

In testimony whereof witness rnyhand this 15 3d day of August, 1891.

GEO. D. COLEMAN.

In presence of ROBERT BURNS, KNOWLTONV L. AMES. 

